Thank you for your purchase of the Archer’s Mushrooms FFU. Please read these instructions before using the FFU as you may find some helpful answers in the setup, use and maintenance of the unit.

If the shipping crate has been excessively damaged or tampered with, please contact us on and include as many detailed photos as possible.

The crate contains;

1 x FFU Body
1 x H14 Filter
1 x Mesh Pre-Filter
1 x Nylon Pre-Filter
1 x IEC Power Cord
1 x Roll of foam
1 x Roll of Aluminium Tape

Step 1: Remove packaging and inspect the above components.

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Step 2: Ensure FFU is clean inside and out, remove any dust/debris with a microfibre cloth, wipe down with disinfectant spray and allow to dry. 

Step 3:  On the filter element note the position of the arrow. Lay the filter with the arrow pointing down onto a flat surface. Slot the body of the FFU onto the filter. Make sure the retaining clamps aren’t pinched between the body and the filter.  

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Step 4: FFU’s have no top or bottom, you are free to select which orientation works best for your plug position. Once selected, ensure the base of the filter is flush with the base of the body

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Step 5: Secure the 4 clamps to the filter face.  The clamping force may distort the filter lip, this is necessary to make a tight seal.

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Step 6: Take 2 strips of the foam tape provided and cut to the approximate width of the FFU. Adhere one strip to the base of the body and one to the base of the filter. 

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Step 7: You can optionally run a single strip of aluminium tape to seal the filter frame with the body of the FFU. This is only required if you detect a leak between the FFU body and filter.

Step 8: Position filter at your work station. Don’t position the FFU flush back against a wall as this may obstruct the airflow intakeLeave a minimum air intake gap of 50 – 100mm.

Step 9: Check the speed controller is in the off position and plug the unit in. Adjust to the setting you require by toggling the speed controller from Off to Low, Medium, or High.  Low should be sufficient for mycological use, as the filter ages and fills up you will need to adjust to medium and high to achieve the same speed level.

Maintenance Practices

To ensure the FFU’s longevity, it is recommended that periodic inspections of your prefilter are undertaken.

To clean pre-filter, remove from its retaining clamps. Holding the filter shake and tap to release the accumulated dust. If the filter is still dirty, wash in warm soapy water and dry completely before following Step 9 to re-fit the pre-filter. Do not machine wash.

The main filter is consumable and cannot be cleaned.

The nature of the FFU means it has some vibration from the fan motor, therefore, periodic checks of the security of the clamps and screws around the body is advisable.

Replacing The Filter

Step 1: Disconnect power and place the unit filter face down.

Step 2: Remove the sealing tape (if applied) between the filter and the body.

Step 3: Unclamp the 4 clamps and again lift the body up and away from the filter face.

Step 4: The used filter is a combination of aluminium, epoxy, and fibreglass. With this information, contact your local authority to find the most suitable way of recycling or disposal of the filter.

Step 5: Source a replacement filter, available at Archer’s Mushrooms.

Step 6: Using a microfibre cloth, thoroughly clean the inside of the body, be cautious of sharp screws and corners. Reach around the fan mounting panel and clean each blade of the impellor. Wipe down the inside of the body with disinfectant spray. Ensure body is thoroughly dry.

Step 7: Follow setup instructions from Step 3 on how to re-fit the filter to the body.


How long will the filter last?

A lot of factors determine a filters life length, if your environment is relatively clean, you can expect several years of use out of your filter. The minimum should be around 3000 hours of use. If you are working in a less-suited environment, this may reduce the life of the filter.

Pre-filters are expected to outlast the main filter providing it is maintained as recommended.

How will I know when my filter requires replacement?

You may notice a gradual drop in airspeed. The fan may sound as though it is labouring. You may start noticing a higher rate of contamination in your grow.

How long will the fan motor last?

If you maintain your FFU as recommended in the above instruction, your fan and speed controller will last many filter changes.

Is there a warranty?

There is a one-year warranty on the body, fan, and speed controller. Filters are not included in the warranty as they have a variable lifespan contingent on usage. 

I want to return the FFU, how can I do that?

If the FFU is faulty or damaged upon arrival, a replacement of parts, an exchange or refund at no additional cost will be offered.

If the FFU is damaged due to a repair being made without consultation, spare parts may be chargeable. Please note, attempting to fix the FFU without prior consultation will void the warranty.

If you change your mind about the purchase of your FFU within 14 days and so long as the FFU is undamaged, in its original packaging and unused including the filter. A full refund will be provided; however, the cost of re-delivery of the unit using the same level of service and insurance as when it was sent will be the customers responsibility.


The airflow feels weak

FFU’s don’t blow air out like a fan, the air is only coming out at approximately 0.5m/s. So long as a lighter flame bends back approximately 90 degrees when held up to the filter face it’s more than sufficient.  Some things to check are;

  • Is the filter on the right way round? The red arrow should be pointing towards you in the flow of air.
  • Is the speed controller on the correct setting? Adjust up or down to suit requirement.
  • Is there air leaking around the any of the gasket? Seal with the provided tape.
  • Is the pre-filter full of dust? Wash according to maintenance practices.
  • How much use has the filter had? If the above points have been addressed, a replacement main filter may be required.

The FFU won’t turn on

  • Has the main plug been turned off? If so, turn back on at the spur.
  • Has the IEC power cord fallen out of the back of the FFU? If so, it will require re-fitting.
  • Is the speed controller making firm clicks or is it just spinning? Replace speed controller.

Thank you again for your purchase, If you have any additional questions, concerns, or need further assistance setting the FFU up, please don’t hesitate to contact us.

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